jQuery Migrate是应用迁移辅助插件，是用于高级版本兼容低级版本辅助插件。未压缩版本调试窗口显示解决方案。若不想修改可直接使用min版。


jquery-migrate-1.4.1.min.js	存在 jq 1.8.3- 旧代码	用于	jq 1.9-3.0
jquery-migrate-3.4.0.min.js	存在 jq 1.9+   旧代码	用于	jq 3.0+

存在 jq 1.8.3- 旧代码
<script src="http://code.jquery.com/jquery-1.12.4.min.js"></script>
<script src="http://code.jquery.com/jquery-migrate-1.4.1.js"></script>

存在 jq 1.9+   旧代码
<script src="https://code.jquery.com/jquery-3.6.0.js"></script>
<script src="https://code.jquery.com/jquery-migrate-3.4.0.js"></script>

jQuery Migrate Plugin
We have created the jQuery Migrate plugin to simplify the transition from older versions of jQuery. The plugin restores deprecated features and behaviors so that older code will still run properly on newer versions of jQuery. Use the uncompressed development version to diagnose compatibility issues, it will generate warnings on the console that you can use to identify and fix problems. Use the compressed production version to simply fix compatibility issues without generating console warnings.

There are two versions of Migrate. The first will help you update your pre-1.9 jQuery code to jQuery 1.9 up to 3.0. You can get that version here:
jQuery Migrate 1.4.1

The second version helps you update code to run on jQuery 3.0 or higher, once you have used Migrate 1.x and upgraded to jQuery 1.9 or higher:
jQuery Migrate 3.4.0